VIEW ARTICLE

Disease Control and Pest Management

Effect of Gliocladium virens on Pythium ultimum, Rhizoctonia solani, and Damping-Off of Cotton Seedlings. C. R. Howell, Research plant pathologist, USDA, ARS, National Cotton Pathology Research Laboratory, P.O. Drawer JF, College Station, TX 77841; Phytopathology 72:496-498. Accepted for publication 20 July 1981. This article is in the public domain and not copyrightable. It may be freely with customary crediting of the source. The American Phytopathological Society, 1981.. DOI: 10.1094/Phyto-72-496.

A strain of Gliocladium virens isolated from the parasitized hyphae of Rhizoctonia solani, significantly suppressed damping-off incited in cotton seedlings by this pathogen and by Pythium ultimum when the antagonist was placed with cottonseed planted in infested soil. Treatment with G. virens more than doubled the number of surviving cotton seedlings grown in soil infested with either pathogen. G. virens parasitized R. solani by coiling around and penetrating the hyphae. P. ultimum was not parasitized by G. virens, but was strongly inhibited by antibiosis. Treatment of soil infested with propagules of R. solani or P. ultimum with G. virens resulted in a 63% reduction in the number of viable R. solani sclerotia after 3 wk of incubation, whereas oospores of P. ultimum were unaffected.